John desmond



(Model.)

J. DESMOND.

Patented Apr. 2, 1895.

. A i Wo THE Nonms 151:58 cd, Puntal llruo., wasumerou, o. ci,

UNITED STATES PATENT EEICE.

JOHN DESMOND, OF NEW YORK, N. Y., ASSIGNOR TO THE NATI-IAN MANUFACTURING COMPANY, OF SAME PLACE.

INJECTOR.

SPECIFICATION forming part of Letters-Patent No. 536,922, dated April 2, l 895. Application filed January l2, 1895. Serial No. 534,661. (Model.)

\ I these, which I will term the primary over liow, is located in the usual overfiow or vacuum chamber of the casing of the injector, while the other, which I will term the secondary overflow, is located in the delivery I or pressure chamber of the instrument, which,

by means of proper pipe connections, communicates directly with the boiler which is to be supplied with water by the injector.

Each of these two overliows is provided with zo valves. It is well known to those skilled in the art, that by closing these valves against the atmosphere, the range of an injector may be widened very materially. The injector will work at higher pressures, and with. feed water of a higher temperature, than would an `instrument, in which these overflows (more especially the secondary overflow) are open, or kept closed only by atmosphericV pressure, as against the partial vacuum produced in 3o the overflow chamber by the action of the injector. My invention inthisdirection has relation to automatically restarting injectors or injectors in which the overflow valves are arranged to automatically7 open and close at the 3 5 proper time.

I am well aware of the fact that it is not new, broadly speaking, to close the overflows of an injector automatically and to keep them closed, while the instrument is in operation,

4o by means of steam pressure, spring actuated valves, or by the pressure of the steam-forced water, which is about to be injected in to the boiler, but the means heretofore used for this purpose have proved inadequate and unreliable.

One of the objects, therefore, of my invention is to provide simple, eective and reliable means toward that end, means which at the same time are to be durable and inexpensive. 5o A further object of my invention is to produce a novel, simple and effective starting mechanism, for the admission of the operating steam into the instrument in place of the usual lever or screw attachments, this mechanism being applicable to an injector whether 5 5 of the particular construction hereinafter described, or not.

With these ends in View, myinvention consists in certain features of construction, and combination of parts which will be found described hereinafter, and more particularly pointed out in the accompanying claims.

The invention may be more fully understood by reference to the accompanying drawings, forming part of this specification, in which- Figure 1 isa longitudinal section of the 1njector. Fig. 2 is a cross section of the casing on line 2-2 of Fig.1,omitting allother parts. Fig. 3 is a cross section of the casing ou line 7o 3-3 of Fig. 1, omitting all other parts.

In the drawings, A represents the easing or shell of the injector. B, C, and D, are the usual threaded necks for the proper steam, water and delivery pipe connections.

F. is the steam nozzle; F, the lifting nozzle;

G, the condensing and delivery nozzles combined.

H is the primary overliow opening between the lifting and the condensing nozzle; H', the So Y cup or plunger shaped primary overflow valve, controlling the overflow passage H2.

I is the secondary overliow valve, controlling the overflow passage I.

B oth of the overow passages unite in a common chamber K, and have their nal outlet in a common overflow branch K. The primary overflow valve H is provided with wings H3, to the top of which is attached a piston H4, by means of a stud and uut. The secondary overliow valve I is provided with wings I2, to the top ofv which is attached piston I3, which I make of larger area than the bottom disk of valve I. These pistons move and are guided in extensions L, and L of the over- 95 flow chambers H2 and I.

boiler and the injector, and N the usual wa- IOO ter valve, to regulate thc admission of the feed water into the injector.

Irrespective of the starting mechanism for the admission of steam into the instrument, which I shall describe later, the operation of the injector is as follows: The natural position of the overflow valve is shown in Fig. l, valve Il seating by gravity,aud valveIopening bygravity. Steam being admitted to nozzle E, by means of the starting mechanism, as illustrated, or by any other suitable means, passes through nozzle F and escapes partly through opening H, lifting the valve II', and passes around through passage I-I2 int-o overiiow branch Ii. A portion of the steam shoots through nozzle G and through overflow branch K into the atmosphere. The steam also passes upward into passage M, exerting a pressure on top of piston I3. The area of this piston I3 being larger than the bottom disk of valve I, this valve I will be kept open at this stage of the operation of the injector. The steam thus nding a free outlet into the atmosphere exhausts the air from the water inlet chamber C and chamber M', and the water will be drawn into the instrument even from a considerable depth. As long as the jet is not properly established, the water will pass through the same channels as did the steam before, and no higher than atmospheric pressure can prevail in the delivery chamber, since this chamber is in open communication with the atmosphere through the open valve I. When the jet is finally established, a vacuum will form in chamber M', and valve Il will drop to its seat. A vacuum will also arise in chamber M, and above the piston I3, producing a differential pressure as between the top of this piston I3, and the bottom of valve I, sufficient to raise valve I, and thus to close the communication between the atmosphere and the delivery chamber. `Now the jet will have attained sufficient force and velocity to open check valve N and to enter the boiler, while valve I will be kept on its seat by the full boiler pressure now prevailing in chamber M2. Should the jet be broken, for example by an interruption of the water supply, the vacuum in chamber M will be destroyed, and steam pressure, then prevailing in chambers M and M', will open valves II and I, and re-establish communication with the atmosphere. The instrument will pass through the same process as in starting, and the jet will re-establish itself automatically, as soon as the water is again within reach of, and supplied, to the instrument.

I give a plunger-like shape to valve Il', so that, in restarting, the steam shall exert pressure on top of piston I3, before valve I'I is fully open. The plunger form will also cause valve H to close down gradually, allowing the jet the necessary time to properly establish itself. The piston on top of valve H will act as a cushion, or dash-pot, in opening and closing.

The startingmechanism consists of aspringactuated piston O, to which is attached (by means of a pin P) a valve R, seating on the steam nozzle E. This piston O moves in a casing S, which, back of the piston, communicates with the atmosphere by means of passages J and J. Passage .I is controlled by a valve U, which is provided with screwthreads and a suitable handle to 4manipulate it. The spring is just strong enough to help 11e-seating the valve R, when necessary, but is not to be of sufficient strength to resist even the lowest steam pressure,at which the injector is expected to operate. The area of the piston is slightlylargerthan that of valve R. When valve U is open, the pressure bctween the piston and the back of the casing S, and caused by the leakage of steam past the piston and into the space at rear between the piston and the casing S, will be relieved, and steam pressure from B will force back the piston, open valve R and admit the steam to nozzle E. On closing valve U, and thus allowing steam pressure to accumulate back of the piston, the spring will re-seat valve R, and stop the admission of steam to the instrumeut, since the pressures in front and at the back of the piston will then be equalized.

- The last above-described feature is described in connection with an automatically restarting injector, but, as hereinbefore stated it is equally useful with, and applicable to, other types of injectors. I have also shown the particular construction preferred by me for carrying my improvements into effect, but it will be evident, that the same may be varied, more particularly in the direction of the construction and arrangement ot' the several valves, without thereby departing from the spirit and scope of my invention. For this reason I do not desire to limit myself strictly to the construction herein set forth, but

What I claim as new, and desire to secure by Letters Patent, is

l. In an injector, a primary overflow Valve located in the vacuum chamber of theinstrument, opened by the force of the primary overflow and closed by atmospheric pressure, when the jet is properly formed, a secondary over- Iiow valve located in the pressure or delivery chamber, and a by-pass or communicating passage between the vacuum chamber and a space above the said secondary overflow valve, whereby the latter will be opened bythe force of the primary overflow, closed by the pressure of the steam forced water on the bottom of the valve, aided by the vacuum above the valve, substantially as and for the purposes Set forth.

2. In an injector, a primary overflow valve, opened by the force of the primary overflow and closed by atmospheric pressure, when the jet is formed, and a secondary overflow valve opened by the force of the primary overflow,

and closed by the pressure of the steam forced water, the two valves being disconnected and separate from one another, located in sepa- ICO IIO

stantially as and for the purposes hereinbe-A fore set forth.

4. In an injector, the combination with the vacuum chamber of a plunger-shaped primary overoW valve H having a piston H4,

which acts as a cushion, preventing the too sudden opening or closing of the valve, substantially as described.

5. In an injector, the combination with the pressure or delivery chamber, of a secondary overflow valve, having a piston 13 of larger diameter than the valve-disk, and a passage .between the vacuum chamber of the injectory and the top of said piston, as and for the purposes set forth.

6. In an injector, the combination, with primary and secondary overflow valves, and the pistons attached thereto, of the cylinder extensions L and L to serve as guides for the pistons, substantially as specified.

7. In a starting mechanism for injectors, the combination with the piston O, of a valve R of smaller diameter, a spring, relief opening T and valve U, substantially as described and specified.

In testimony whereof I have hereunto set my hand this 10th day of January, 1895.

JOHN DESMOND.

Witnesses:

CHARLES JUDGE, ADOLPH BARGEBUHR. 

